Means for well drilling



June 17, 1958 o. COLQUITT MEANS FOR WELL DRILLING Fil ed March 7, 1956 2 Sheets-Shae}. l

' "TEIIWEIIJI June 1958 o. COLQUITT MEANS FOR WELL DRILLING 2 Sheets-Sheet 2 Filed March 7, 1956 INVENTOR. fla/i (a4 au/rr MEANS FOR WELL DRILLING Odie Colquitt, Denver, Colo., assignor to The Winter- Weiss Company, Denver, Colo.

Application March 7, 1956, Serial No. 569,987

3 Claims. ((11. 255-24) This invention relates to well drilling, and more particularly to the type of well drilling used for relatively large diameter water wells and known as reverse flow drilling, such as described in applicants prior Patent No. 2,657,015.

In reverse flow drilling the well is maintained filled with water which flows into the well at the ground surface and is drawn from the well together with the drill cuttings, mud, rocks, etc. through the drill pipe. Such a method has been found highly satisfactory in drilling comparatively shallow wells. For deeper wells, however, it has been diflicult to lift the mud, rocks, debris and water through the drill pipe due to internal friction in the long drilling string of pipe.

The principal object of this invention is to provide means for drilling relatively deep wells by the reverse flow method in which the ascending mud, water and debris will be aerated as it approaches the surface so as to decrease the density thereof, thereby relieving the weight of the ascending fluid column and decreasing the friction on the drill pipe so as to make deep drilling commercially practical.

Another object of the invention is to provide highly efiicient means for furnishing compressed air to the rorating drill string of drill pipe at any desired depth in the well, and to so construct the air supply means that it will not interfere in any way with the normal well drilling operations.

Other objects and advantages reside in the detail construction of the invention, which is designed for simplicity, economy, and efiiciency. These will become more apparent from the following description.

In the following detailed description of the invention, reference is had to the accompanying drawing which forms a part hereof. Like numerals refer to like parts in all views of the drawing and throughout the description.

In the drawing:

Fig. 1 is a fragmentary side view of the upper portion of a string well drilling mechanism, illustrating the invention applied thereto;

Pig. 2 is a continuation of Fig. 1, illustrating a lower atent portion of the tool string partially broken away to show the interior construction;

Fig. 3 is an enlarged fragmentary vertical section, taken on the line 3-3, Fig. 1;

Figs. 4 and 5 are cross-sections, taken on the lines 4-4 and 5-5, respectively, Fig. 1; and

Figs. 6 and 7 are similar cross-sections, taken on the lines 6-6 and 7-7, respectively, Fig. 2.

This invention applies to a well drilling rig or" the type in which a Kelly, to which the string of drill pipe is attached, is suspended from a swivel supported by the draw works of the rig. The kelley is rotated by any suitable conventional rotary table mechanism and a stationary suction pipe extends through the swivel and into the kelly, the latter being vertically slidable on the suction tube.

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The present invention employs aswivel housing 10 which is supported from the draw works by means of suitable hangers 11. The swivel housing is provided with oppositely projecting bracket arms 36 which engage slides in the draw works to prevent rotation of the housing as described in .applicants prior Patent No. 2,657,015.

The swivel housing is provided with upper and lower annular ball races in which suitable steel thrust balls 12 travel. The thrust balls rotatably support a swivel core 13 within the swivel housing 10.

v A cylindrical bearing sleeve 14 is sweated or otherwise secured about the core 13. The bearing sleeve 14 is sealed to the housing 10 above and below the ball races therein by means of suitable expansive, annular sealing gaskets 15. The core 13 is provided with any suitable wear liners 16 which are retained in place therein by means of a threaded, annular, spanner cap 17.

The core 13 is positioned about a stationary suction pipe 13 and is both vertically and rotatably movable on the suction pipe 18. The suction pipe 18 is supported from a suction fitting 47 leading to the intake of a suction pump .as described in applicants said prior Patent No. 2,657,015. A

The core 13 is provided with an annular, internal cavity which forms an air jacket 19 therein. The air jacket 19 opens through the bottom of the core 13 through spaced-apart air ports 20. Air is supplied to the air jacket 19 through a compressed air pipe 21, which in actual practice would be connected through the medium of a flexible hose with a suitable air compressor.

The air pipe 21 is threaded into an air intake boss 22 on the swivel housing 10 which communicates with an annular air chamber 49 surrounding the core 13. Air is continuously admitted to the air jacket 19 from the chamber 49 during the rotation of the core through air passages 23. The air enters the swivel 10 between the upper and lower sets of sealing gaskets 15 so that the latter act to prevent the escape of air from between the swivel housing and the swivel core.

The kelly of the present invention comprises a Kelly tube 24 within which the suction pipe 18 terminates. Vertically positioned angle irons are welded in axial alignment and spacer-apart relation to the external surface of the Kelly tube 24 to form a substantially square cross-section. Two of these angle irons, which will be designated as guide angles 25, terminate in spaced relation to the upper and lower extremities of the Kelly tube 24. The remaining two angle irons, which will be herein designated as air conducting angles 26, extend the full length of the Kelly tube 24 and are welded to a lower Kelly tube flange 27 and an upper Kelly tube flange 28. The air conducting angles 26 communicate through the flanges 27 and 28 through triangular air ports 29 formed therein.

The upper flange 28 of the Kelly tube 24 is bolted to a lower flange 30 on the swivel core 13 by means of suitable attachment bolts 31 so that the two triangular ports 29 therein will align with two of the air ports 26 of the core 13 so that air will be conducted from the air jacket 19 through the air conducting angles 26 and through the lower Kelly flange 27. As illustrated, there are two pairs of oppositely-positioned ports 20 in the core 13 so that the Kelly flange 28 with its two oppositely positioned ports 29 can be secured in either of two positions at to each other.

The Kelly tube 24 passes through an opening in a conventional rotary drilling table and is locked against rotation relative to the table by means of slips which form a rectangular opening corresponding to the rectangular cross-section of the Kelly tube The con- I Q5 7 struction and use of rotary tables, slips, and square Kelly bars is well known in the art. v

The lower Kelly flange 27 is bolted to the upper 1 section of a plurality ofsectionsof drill pipe .32 by 'means of suitable bolts 35; 'Each of the sections of Whena string of the sections 32 are bolted together,

the smaller'openings in the flanges 33 thereof align with each other so thatair can flow from the air jacket 13 through the air tubes 34 of the entire string.

-.The string of sections terminate in an air-jacketed section'37 which is bolted to 'thelowermost section of the string by means of suitable attachment bolts 38. The air-jacketed section 37' is provided with air tubes 4 39 which communicate, throughports in an upper flange 40 thereon, with the air tubes 34 of the next above section. The fair-tubes 391on the jacketed section 37 are provided with 'check valves'41 of any suitable conventional type which act to prevent upward flow through the air tubes. T

The check valves 41 discharge through nipples 42 into'a cylindrical air manifold- 43 sealed to 'and'circurn-I ferentia'lly' surrounding the air-jacketed tube 37. A

plurality of air jet 'openings 44 are formed through the jacketed section 37 within the manifold 43. a

- The jacketed section 37- terminates at its lower extremity reverse flow variety. 1

In use, the well is completely filled with water and in a conventional pipe flange 45 from which the usual drill pipe sections of the' drilling string, indicated at' 46, are suspended. The latter drillpipe sections extend V to and terminate in any suitable well drilling bit of the the air-manifold 43 is positioned in the drilling string intermediate the drilland .theground surface. .Water is continuously supplied into the mouthof the well, indicatedin broken line at '48 in' Fig. l. .Thiswaterflows to the bottom of the well thence :throughjthe" drilling bit and upwardly through the drilling string 46, the jacketed section 37, the sections 32,,the Kelly; tube 2.4,,the suction.

of the ascending column of mud and water up to the:

ground. surface is substantially balanced by the weight of the waterfilling thelwell. The only head which must be overcome by'atmospheric pressure, when the suction pump'icreates a partial vacuum over the ascending column, is from the ground surface to the pump.

thereof so as to reduce the friction on the drill pipe and allow free flow to the surface.

Should the air pressure fail, the hydraulic pressure in the well would tend to force mud upwardly in the air pipes. This is prevented, however, by the check valves 41 which close whenever the hydraulic pressure exceeds the pneumatic pressure.

While a specific form of the improvement has been described and illustrated herein, it is desired to be understood that the same may be varied, within the scope of the appended claims, without departing from the spirit of the invention Having thus, described the invention, what is claimed and desired secured by Letters Patent is:

1. Means for aerating a rising column of mud in a well drilling apparatus of the reverse flow type, having a stationary vertical suction .pipe suspended over a well comprising: an annular hollow swivel core 'slidably surrounding said suction pipe; an annular swivel housing surrounding said swivel core, the interior of said housing being in communication with the hollow interior of said swivel core; thrust bearings between said housing and said core, said hearings allowing rotation of said core in said housing and preventing relative axialmovement therebetween; means for supporting said housing on said suction pipe; means for admitting air under pressure to said housing; a Kelly tube suspended from said core about said suction pipe for conducting mud to the interior of said suction pipe; a longitudinally extending air conduit on the exterior 'ofsaid Kelly tube in communication at its upper extremity with the hollow interior of said core; a plurality of connected sections of drill pipe secured to'and suspended from saidKelly tube for conducting mud intothe interior of said Kelly tube; a longitudinally extending air tube mounted on the exterior of each section of urnrpi e, said airtubes being in communication with each otherand .withthe air conduit on said Kelly-tube; a cylindrical air manifold surrounding one of the lowermost sections of drillpipe, said manifold being of larger diameter than saidlatter section; means sealing each extremity of said air manifold to said latter section toffornra closed, cylindrical air chamber thereabout, the. air tubes "of the superimposed sections being in-coinmunicationwvith said chamber tosupply air thereto from the hollow interiorofsaid swivel core,

there being jet openings. in the wall of saidlatter drill pipe section, directing air jets-from said chamber" into the interior of said latter sectign; and'a tubular drilling stringattached to and suspended from said latter section for: conducting mud from said .well to said connected 1 sections of drill pipe.

However, there is also friction between the mud and 'drill pipe to contend with andas the well deepens this friction retards the upward'to such an extent-as to make further drilling impractical. f

7 However, with the use of this invention, this difiiculty is overcome for if the manifold 43 be positioned intermediate the surface and the'drillit Will be found that debris to reduce the density and'increase the buoyancy 2.1A well drilling apparatus as described in claim '1 in which the external air passagconsaid' Kelly tube comprises an angle iron welded along its edges-to said Kelly tube so that the interior of said iron will form said air passage, and so that said angle iron will form a projection on said Kelly. tube through'which'rotation may be imparted to said Kelly tube.

3. Means for aerating a rising column of mud as described in claim 1 having a check valve positioned in the path of flow from said air tubes to said air chamber to prevent reverse flow from said chamber to said tubes.

' References Cited in the file otthis patent UNITED STATES PATENTS Durbrow July 3, 1888 

